Level sensor with alarm
US5132669A · kind A · utility
Inventor
Key dates
| Filing date | Sep 18, 1990 |
| Grant date | Jul 21, 1992 |
| Priority date | — |
| Expiry date | Sep 18, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B21/182
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An alarm system for use in a salt-brine tank of a water softener has a sensor including a stem member having a lower end received in the bed of salt within the salt-brine tank and an upper end projecting above the bed of salt. An spaced pair of electrodes are supported at the stem member upper end and are responsive to direct contact with a brine solution inside the tank for generating the signal indicative of an abnormal condition. An electronic circuit is coupled to the sensor for generating an alarm which includes two counters coupled to a clock circuit such that any alarm indicative of the abnormal condition is delayed for a predetermined period of time after the sensor signals the abnormal condition, and the alarm is generated as spaced, short bursts of sound, the spacing between the bursts of sound being greater than the duration of the bursts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.